Method of producing conduits, &amp;c



T. E. MURRAY.

METHOD OF PRODUCING CONDUITS, &c.

APPLICATION FILED JULY 17. 1920.

1,399,308. Patented Dec. 6, 1921.

2 SHEETS-SHEET I- APPLICATIOi FILED JULY I7, 1920.

Patented Dec. 6, 1921.

2 SHEE S-SHEET 2.

UNITED STATES mow-n. MURRAY, 01 BROOKLYN, NEW YORK.

PATENT OFF ICE.

METHOD PRODUCING CONDUITS, 8w.

Application filed July 17,

1 To all whom it may concern.

Be it known that I, THOMAS E. MURRAY,

a a citizen of the United States, residing at Brooklyn in the county of Kings and State of New York, have invented a certain new and useful Improvement in Methods of Producing Conduits, &c., of which the following is a specification.

The invention is a method of producing conduits, pipes, tubes or ducts, and, if desired, in the place where said conduits arefrom the mandrel and extended. Fig.. 3

shows the extended coil or core enveloped in smooth flexible material such as paper. Fig. 4 shows the material in plastic state applied to the wrapped core to form a wall thereon-a portion of this figure being broken away to show the coil and wrapping.

k Fig. 5 shows the completed conduit after hardening of the material and withdrawal of the coil. Fig. 6 illustrates the method of producing rogressively and in sections a conduit of esired len h. Fig. 7 is an end view-of agroup ofour wrgpped coils or cores united by bands of sti paper to support the same in relative positlon in forming a multiple conduit. Fig. 8 is a side elevation of the united cores of Fig. 6 before the application thereto of the plastic material. Fig. 9 shows partly in section and partly in elevation one end of one of the cores and adjacent parts of the conduit of Fig. 7.

Similar numbers and letters of referenc indicate like arts.

Referring rst to Figs. 1 to 5, inclusive, in order to make the conduit shown in Fig. 5, I proceed as follows:

Upon a cylindrical mandrel 1 of a dlameter substantially the same as that of the inner diameter of the desired conduit, I wind a helical coil 2 of wire--the turns being preferably placed close together so that the mandrel may be madeconveniently short. The number of turns in the coil 2 will depend upon the desired length of Specification of Letters Patent.

1920. Serial lio. 896,956.

the conduit or conduit section to be made, and also upon the distance between the turns when the coil is extended longitudinally to produce said length. A coil when extended longitudinally is illustrated in Fig. 2, but it is to be understood that the selected length is furtherto be governed Patented Dec. 6, .1921.

by the requirement that the distance between the turns shall not be so great as to prevent a wrapp ng 3 of paper or other thin, smooth, flexible material being wound thereon, as

shown in Fig. 3, and in any suitable manner secured in place.

To the 1 core formed of coil and wrapping I (Fig. 3) I apply by molding or in any other convenient way material 4, such as cement, in a plastic state to embed said core and to form the wall of the conduit. When this material becomes sufficiently hard, I withdraw from it the coil 2 longitudinally, as indicated by the arrow (1. The smooth wrapping 3. permits of this withdrawal and I t prevents engagement of the coil with the conduit wall. After the withdrawal of the c011, this wrapping may be left in the conduit or beremove d .in any suitable way.

The final result is the completed cement conduit of desired diameter, and as shown inFig.5.

Where a conduit longer than that which can be conveniently made on a single core is desired, I can pro uce the same in successive sections and continuously for an desired length. To this end, as shown in ig. 6, instead of withdrawing the coil entirely from the completed conduit thereon, I may withdraw it for the greater portion of its length, leaving the remainder still within the conduit to support the withdrawn portion in line therewith. I then place upon the rotruding portion 5 a wrapping 3, as be ore, and then applyl the plastic material 4* so as to contact wt and correspond in diameter to the wall 4 of the completed section and to be a continuation thereof. When the additional wall 4* is hardened, I once more withdraw the coil partially, and roceed as be fore, thus formin section a the conduit until t e entire desired length is completed. Instead of leaving apportion of the core within the first section of the conduitto form asupport, as described, I may withdraw the whole core and support it in any other suitable wa -in contact and end r section of the plastic material to form the wall of the second section in continuation of the wall of the first section, as already ex lained.

' When I wish to make a multiple conduit, I roceed as follows: see Figs. 7, 8 and 9, in w 'ch a group of ,four ducts is illustrated.

- Four wrapped cores A, B, 'C, D produced as already set forth, are connected by bands of stiff cardboard or paper so as to stand preferably, as here shown, relatively paralel and mutually supporting one another in position; that is to say, the cores A, B are connected by the continuous band 6 which asses around both cores and has its parts rought into contact between said cores and connected together by any suitable fastener, such as shown at 7. The cores C, D are con- -nected by the band 8 in the same way. The

' cores A, C and B, D are-connected by similar bands 9 and 10, which stand at right an- 'gles to the bands 6, 8; Finally, around the group of cores is secured a band 11. The

' a protecting wall 12-all of t lastlc material 4 is then applied so as to 11 all the spaces between the cores and to extend outwardly beyondjthe group to form bands then being left embedded in said material. The coils are finallywithdrawn, leav- I ing the quadruple conduit finished;

Actual production on an extended scale has already shown that'conduits for electric cables or wires can thus be made cheaply and f rapidly. Any suitable material ca able of beln rendered plastic and of a terward har ening may be used.

I claim:

1. The method of making progressivel and in consecutive sections a conduit, whic thereo e supportingconsists in, first, producing a helical wire coil; second, enveloping said coil in a wrapr of smooth flexible material; third, moldmg a wall of material in plastic state upon said wrapped coil as acore and allowing said material to harden; fourth, withdrawing said coil from itshardened envelop and supporting the same in contact with the end gation of the axis of said. envelop; fi

wallof the conduit previously'made, and

seventh, withdrawing said coil and repeat ing the aforesaid steps until a conduit of desired length is obtained.

with its longitudinal axis in iptrolon- I h, ap+ plyinglto said withdrawn coil a wrapper f'of 2. The method of making a multiple c'on I duit, which consists in, first, producing a plurality of helical wire coils; second, enveloping smooth flexible material; third, disposing each of said coils in a wrapper of said wrapped coils'in a group parallel to one another and supporting'one u n the other. in said position; fourth, fil mg the s aces'between said wrapped coils with plast1c material and covering. said groupof coils.

with an outer layer of the same and allowing said material to harden, and fifth, withdrawing said coils.

In testimony whereof I have afiixed my signature in presence of two witnesses.

Witnesses:

: Gnn'rannn T. Pon'rna,

MAY T. MoGARRY;

THOMAS E. MURRAY. 1 

